In the title complex, [Ca(C7H5O2)2(C2H6OS)]n, the Ca2+ ion (site symmetry m..) is surrounded by eight O atoms, six from two bridging–chelating tridentate benzoate carboxyl groups and two from a bridging dimethyl sulfoxide molecule (point group symmetry m..), giving an irregular coordination geometry [Ca—O bond length range = 2.345 (2)–2.524 (2) Å]. One-dimensional coordination complex chains extending parallel to c are generated in which the triply μ2-O-bridged Ca2+ cations are separated by 3.6401 (5) Å. In the crystal, weak intrachain C—H...π hydrogen bonds are present between the methyl H atoms of the dimethyl sulfoxide molecules as donors and the aromatic rings as acceptors [C—H...Cg = 3.790 (4) Å].